The mobile version of the forum is up:
http://mobile.forum.phonedifferent.com
I have also been working on an iPhone-app-like version, but that's looking pretty tough for me right now so it's going to wait a bit.
In the meantime, I just used our standard mobile template but uppped the font size so that it would be more readable on the iPhone. The result is it look pretty crappy on PocketIE, but i guess that's ok. It also doesn't display much in landscape mode.
Anyhow, suggestions for tweaks and changes to the mobile forum to make is more iPhone friendly are welcome. On the list right now is increasing font size and image side for the header bits.